W124 300E electrical gremilns

[Allybasher]

My 300E is suffering recently from various strange electrical issues. This week, I was driving to work in the rain, firstly it started to misfire, then the ABS light came on, the wipers stopped then it cut out and all the electrics were dead. I recovered it to a local garage who still have it and can't trace the fault. Firstly, any suggestions? I thought it was the alternator but apparently it isn't. Secondly the recovery truck driver told me that the cars are fitted with a loom which degrades until beyond repair. Is this true? If do anyone want to buy a dead 300E?

 

[Cronzi]

Voltage regulator from the alternator is done, replace it

 

[carat 3.6]

Might be the ovp relay, it will need changing at some point anyway. It's behind the battery to the right, silver with a 10amp fuse on it.

 

[kingdave]

The loom issue should not impact you in a 300e

It appears post-facelift cars have the dodgy insulation so it's mostly E280, E320 and to a lesser degree E300D. Mostly 6 cylinder cars after 1995

 

[kth286]

Try never to take a Merc to a local garage as they will hardly ever have experience of working on them.

As said, it is likely the OVP relay, as the solder joints decay on the circuits.

 

[Allybasher]

Thanks for that guys, it actually turned out to be the alternator voltage regulator so nothing too dramatic. That's good news about the wiring loom, thanks for the reassurance on that. Unfortunately it was Sod's law with the garage, it packer up on my 50 mile commute so it got recovered to the garage next door to work.

 

[MercMental]

Insulation problems trace to M104 motors

 

[carat 3.6]

Insulation problems trace to M104 motors

m111 looms can be just as bad.

 

[ray_hennig]

Insulation problems trace to M104 motors

Early M104 wiring was OK.

RayH